1. Field of the Invention
The present invention relates generally to the field of mobile robotics.
2. Background Art
Robots are often used to perform tasks that are inherently dangerous for humans. For example, robots have been used to explore dangerous caverns as well as disarm explosive devices. Robots may also be deployed in various hazardous environments where the ambient conditions are not conducive for sustaining human life.
All-terrain, mobile robotic vehicles are known and have been discussed extensively in the literature. U.S. Pat. No. 5,022,812 (Coughlin, et al.), U.S. Pat. No. 4,932,831 (White et al.), and U.S. Pat. No. 5,443,354 (Stone et al.) are representative and are hereby incorporated by reference. The IRobot® PackBot™ and Foster-Miller® Talon™ are two examples of the current state of the art. IRobot® is a developer of robotic and artificial intelligence technology based in Burlington, Mass. Foster-Miller® is an engineering and technology development firm principally located in Watham, Mass., and recently purchased as an independent, wholly owned subsidiary of the British company QinetiQ, Inc. Both robots are capable of navigating up stairs and maneuvering over many kinds of rugged terrain, and can easily self-right themselves if flipped over. However, both these robots suffer from a common drawback. Generally, both robots operate optimally only when they are not burdened with a significant payload. For these robots, having to carry useful payloads can significantly complicate and fundamentally compromise their maneuverability and overall effectiveness.
Robotic torsos and robotic arms capable of lifting payloads of various weights are known. U.S. Pat. No. 4,024,961 (Stolpe), U.S. Pat. No. 4,565,487 (Kroczynski), U.S. Pat. No. 5,394,766 (Johnson et al.) and U.S. Pat. No. 6,408,225 (Ortmeier, et al.) are representative and are hereby incorporated by reference. The PackBot™ Explosive Ordinance Disposal (“EOD”), for example, wields a cumbersome, but useful, 7-DOF (Degrees of Freedom, or actuators) robotic arm. However, if the PackBot™ falls over, righting this robot could do significant damage to the arm and can be a long, slow process.
Applying Dynamic Balancing Behavior (“DBB”) to enhance maneuverability and navigation of an apparatus is a known technique and has been addressed extensively in the literature. Illustrative of this literature is U.S. Pat. No. 6,527,071 (Villedieu), U.S. Pat. No. 6,330,494 (Yamamoto), and Raibert, M. H., Legged Robots that Balance, MIT Press, Cambridge, Mass., 1986, all of which are incorporated herein by reference. Particularly useful and incorporated herein by reference, is U.S. Pat. No. 6,302,230 (Kamen, et al.) This patent is related to the Segway® device. Although Dynamic Balancing Behavior (“DBB”) has been around for many years, the underlying technology used by the Segway® has only been applied to transporters designed for easily navigable terrain. Further, Segway®-like systems are designed for limited-purpose, human use and are thus equipped with safety features that diminish the marvels of the underlying DBB technology. Finally, Segway® transporters must maintain a strict vertical balance to avoid throwing their riders, and maximum speeds are strictly enforced.
Various systems for controlling mobile robots, such as the software architecture disclosed in U.S. Pat. No. 6,535,793 (Allard), are generally known to those skilled in the art. One such standard architecture for mobile robot control is articulated and set forth in the Joint Architecture for Unmanned Systems (JAUS) documentation. JAUS is mandated for use by all of the programs in the Joint Ground Robotics Enterprise (JGRE). This initiative is designed to develop an architecture for the Domain of Unmanned Systems (DUS). JAUS is an upper level design for the interfaces within the domain of Unmanned Ground Vehicles (UGS). It is a component based, message-passing architecture that specifies data formats and methods of communication among computing nodes. It defines messages and component behaviors that are independent of technology, computer hardware, operator use, and vehicle platforms and isolated from mission.
JAUS uses the Society of Automotive Engineers Generic Open Architecture (SAE GOA) framework to classify the interfaces. It complies with the Joint Technical Architecture as well as the Joint Technical Architecture—Army. JAUS is prescriptive, as opposed to descriptive, and is sufficiently flexible to accommodate technology advances. JAUS can be used by any Unmanned System—Air, Ground, Surface, or Underwater—be it commercial or military.
Further information on the Joint Architecture for Unmanned Ground Systems (“JAUS”) can be found at http://www.jauswg.org. This website features the definitive descriptions and publications for elements related to the JAUS standard.